The invention relates to power-driven conveyor systems generally and, more particularly to apparatus and methods for conveying tires delivered from opposing rows of tire curing presses onto a central conveyor.
One of the last steps in the manufacture of a tire is molding and curing. In this step, the external rubber surfaces on a “green tire” are shaped under pressure and cured at elevated temperature in a tire press. A typical tire plant has many tire presses operating simultaneously to mold a variety of tires. The tires exiting the presses are discharged onto short discharge conveyors, such as gravity-roller conveyors, which deliver the tires onto a long main conveyor at various positions along its length. Because there may be many tire presses and many discharge conveyors feeding tires to the main conveyor along its length, collisions between tires delivered to the main conveyor from different tire presses are common. Sometimes the collisions can cause the flexible tires to jam within the confines of the main conveyor, which may result in deformation of the tires. Releasing a jam requires manual intervention, which is time-consuming and may be too late to avoid permanent deformation of the tires. Closed-loop controls that sense the positions of the tires and control the speed of the main conveyor or the discharge of tires onto the main conveyor are sometimes used to prevent jams. But closed-loop controls are complex with a multitude of sensors.
Thus, there is a need for a simple jam-free conveyor system for conveying tires received from a multiplicity of tire presses.